Neurooncology is a branch of medicine that concerns cancers of the brain and spinal cord. Cancers of the nervous system are often severe conditions that eventually become life threatening.
Some examples of these life threatening neurological cancers include astrocytomas, glioblastoma multiforme, glioma, pontine glioma, ependymoma and brain stem tumors. Of the malignant brain cancers, high-grade astrocytoma and gliomas of the brain stem are examples of the most severe diseases, with patients not usually surviving more than a few months without treatment. Survival can be extended with chemotherapy and radiotherapy to a couple of years in some cases.
Cancers of the nervous system may occur as primary tumors or as secondary or metastatic tumors that arise due to cancer that has spread from another part of the body. Primary tumors can occur at any age but they often affect people while they are in their prime. Most primary cancers are more common among males than females, although meningiomas are more common among females. Secondary tumors can spread to the nervous system from another site of origin through metastasis, compression or direct invasion.
Various inherited conditions can lead to the development of brain tumors such as neurofibromatosis, tuberous sclerosis and Turner syndrome. Other factors that are thought to increase the risk of brain cancer include age, exposure to radiation and a weak immune system due to HIV/AIDs or the use of immunosuppressant medications.
The main clinical feature that presents in cases of brain tumor is seizure. Seizure occurs in abut 15% to 20% of intracranial tumor and in about half of patients who have melanoma metastases and tumors that hemorrhage. In the majority of patients with cancer that has spread to the spinal cord, pain is the main symptom. The pain is caused by a reduced blood flow to the spinal cord and traction on the membranes that cover the bone and meninges as well as the nerve roots and nearby tissue.
Diagnosis in neurooncology relies on imaging studies to determine the location, size and extent of the tumor. Computed tomography (CT) and magnetic resonance imaging (MRI) are the most commonly used techniques. Other tests that may be used include positron emission tomography (PET), myelography and angiography. In some cases, a lumbar puncture and analysis of cerebrospinal fluid are required.
The three main treatment approaches to cancers of the central nervous system include chemotherapy, radiotherapy and surgery. Radiotherapy is an important treatment for central nervous system tumors and has been shown to improve survival among those with both primary and metastatic tumors. Chemotherapy and corticosteroids are also commonly used to reduce and control symptoms. Palliative care and end-of-life care are focused on providing symptomatic relief and improving the quality of the life that patients still have remaining.
Reviewed by Sally Robertson, BSc